Final answer:
Yellow pea color is a dominant trait governed by a single gene, and the crossing of two plants that produce yellow peas resulting in green peas suggests Mendelian inheritance from heterozygous parents.
Step-by-step explanation:
Genes are segments of DNA that determine the phenotype of an individual. In the context of Mendel's pea plant experiments, the color of pea seeds is an example of a trait that is determined by a single gene with two alleles.
When two plants that produce yellow peas are crossed and produce green peas, this indicates that the yellow color is a dominant trait while the green color is a recessive trait.
The parents were likely heterozygous, meaning they had one dominant allele (for yellow peas) and one recessive allele (for green peas).
Since the offspring produced green peas, the parents must have both contributed a recessive allele to the offspring.
This type of inheritance pattern is known as simple Mendelian genetics, where traits are determined by dominant and recessive alleles of a single gene.